Indirect measures of pressure, temperature and other thermodynamic characteristics of systems are useful in many contexts and are used in numerous everyday applications. In internal combustion engines, knowledge of the instantaneous pressure and temperature in an engine cylinder assists in the management of parameters that effect engine efficiency and pollution emission, such as variable valve timing, lean burn and minimum timing for optimum torque.
The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named Inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.